Inkbird overshooting heating/cooling

[kxavier_23]

I recently upgraded to a Spike CF10 with the heating/cooling package. I use a 1/3 HP Penguin chiller set to 28 degrees. Using the same Inkbird 308 controller I use on my SS Brebuckets, I am seeing the Inkbird connected to my CF10 constantly overshooting the cooling, then going into a heating cycle. I am using an original Inkbird, not the Spike version.

My other challenge is that I typically run multiple fermenters (2 22 Brewbuckets and now the CF10) so I may be cold crashing while fermenting.

I have seen some threads on controlling via RasberryPi and PIDs, where they are accurate to .1 degree. Just curious if the Pi controllers have better logic to prevent overshooting temps.

 

[WNKbrew]

Nobody? I'll throw in my $0.02. I used to run into same issue with my glycol chiller/internal ss coils, in 1/4 tall and 1/2 barrel kegs.

I learned to leave glycol only 10-15 degrees less than desired fermentation temp. My theory about overshoot is that when probe temp is satisfied and shuts off pump, very cold glycol left in coil continues to cool, causing the overshoot.

Just a theory, my knowledge of thermodynamics, coil length, batch size, glycol temp, ferm temp., probe distance from cooling coil, and their relationship to each other, won't fill a beer glass. Hoping someone else chimes in.

I'll take glycol to 26-28F when I want to CC a fermenter, but I avoid doing so during peak fermentation in other tanks. It's usually a 2-3 day wait, at most. I ferment in my normally cool basement, so after peak fermentation I can shut off glycol flow to a tank while cold crashing others without any real temp rise.

If you must leave glycol at 28F, perhaps reducing flow rates in active fermenters might do the trick, but I believe you'll still leave 28F glycol in coils. Was going to try this myself with valves but once I learned my systems behavior I haven't bothered.